We propose the web-based delivery of an evidence-based medical nutrition training program for medical residents and other postgraduate physician learners. We will develop a comprehensive set of learning modules covering the critical nutrition-related knowledge and practice skills essential for physicians to effectively treat their patients or to counsel them on preventing chronic diseases such as cancer. Each module will cover a tightly focused nutrition topic, allowing physicians to improve their knowledge with modest time investments required. The program will emphasize clinical skill building, translating the most current guidelines and clinical experience into an instructionally sound and user-friendly format. A limitation of existing nutrition instruction is that it covers basic content, but leaves it up to the interpretation of the learner how to put the concepts into practice and apply them to individual patients. The emphasis of the presentation will be on practical applications - how to translate guidelines into providing quality patient care. Physicians completing any learning unit will understand how to implement the guidelines without being encumbered by mechanistic explanations. Nonetheless, in our program basic nutrition information will be available for review as needed. The modular and flexible format of our instructional units will optimize learning efficacy during postgraduate training by facilitating the brief and tightly focused coverage of critical nutrition topics for the increasingly busy health professional. We plan to implement a software strategy that will computer-tailor content delivery based on the learner's pre-existing knowledge. Built-in remediation components based on concurrent monitoring of learning efficacy will strengthen the efficiency of our instructional approach for all learners. We expect that efficient use of the learner's time will increase use and retention of this material. We will evaluate the degree to which physicians change their nutrition practices after using the curriculum. Because of the sophistication in our data collection and tracking system, we can collect anonymous information on the extent physicians utilize important clinical nutrition practices, at baseline and at least 3 months after completing a given module. We expect a very high response rate because the assessment questions will be embedded into the modules dynamically, based on a specific user's learning history. We can continue to poll each user periodically to measure the continuing impact the curriculum has on practice skills. With NCI support we will make the material available to all US medical residents without cost. We will actively promote the curriculum with oncology residency program directors as well as other residencies nationwide. We have been working for many years with a steadily growing group of experienced clinical nutrition educators, and we will collaborate with them to promote clinical nutrition education to the medical trainees they routinely contact.